(1) Field of the Invention
The present invention relates to sensors, and more specifically to a method and apparatus of utilizing a single sensor to indicate the occurrence of many different types of events.
(2) Description of the Prior Art
Due to ongoing research, sensors continue to become smaller and less expensive. There are scenarios where it may be useful and practical to distribute many thousands of sensors in an area to perform various detection and monitoring tasks. Creating a sensor system wherein the sensors are capable of sensing their environment is a fairly simple endeavor. In comparison, however, providing a method for the sensors to transmit information to an end user concerning what the sensors have sensed is far more complicated. One technique for a sensor to provide information to an end user concerning an event that has been sensed is to have a sensor detonate a small explosive charge when certain sensing criteria are determined by the sensor, such as sensing the passing of a certain target signature or sensing a certain chemical. Obviously there are limitations to using explosive charges as indication means. An explosive charge is a single use indication means that can only provide a minimum of details about the occurrence of an event. What is needed is a method and apparatus that enables a sensor with a single use indication means to transmit a greater quantity of information about a single event or a series of events.